4inch Vapour Barrier is to protect the lights. Resists water vapor caused by pressure changes.
Vapour barriers can help control moisture in areas such as basements, ceilings, crawl spaces, floors and walls
6inch Vapour Barrier Product Features for led recessed downlight:
1: Resists water vapor caused by pressure changes.
2: Vapour barriers can help control moisture in areas such as basements, ceilings, crawl spaces, floors and walls
3: Rated max. 90 degrees celsius, polyethylene material

Vapour barriers can help control moisture in areas such as basements, ceilings, crawl spaces, floors and walls